Energy-starved Japan will regain nuclear-powered electricity on Sunday, as the first reactor to be switched on since last year's Fukushima disaster comes online.

Kansai Electric Power Co. Ltd. (KEPCO) told CNN Wednesday that the No. 3 reactor at the country's Ohi Nuclear Power Plant will be activated on July 1 and start providing electricity to western Japan -- which includes Osaka, Japan's second biggest city by July 4. Ohi's No. 4 reactor is also scheduled to resume operations by July 24.

All 50 commercial nuclear reactors in Japan have been offline since May 5 for safety checks. The government has been conducting simulation tests for restarting its nuclear reactors in response to public concerns over their safety in the wake of the crisis at the Fukushima Daiichi nuclear plant last spring.

Before the March 11 disaster, Japan had relied on nuclear energy for about 30% of its electricity needs, according to government figures.

Meanwhile, all but one of Japan's electric companies held their annual shareholders' meetings Wednesday. In Osaka, where KEPCO's board was meeting, protesters gathered outside the venue calling for the closure of all nuclear power plants. KEPCO's largest shareholder, Osaka City, actually proposed closing the plants at some stage in the future as part of a reform of the company, but the motion was voted down, according to KEPCO's public relations office.

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"Now it's the time, the turning point in the energy supply system. I want the management to take a risk (of nuclear safety) into a consideration and aim to establish the new energy supply system," said Toru Hashimoto, the mayor of Osaka, who attended the meeting.

In the capital, shareholders for the Tokyo Electric Power Company (TEPCO) voted to accept one trillion yen (US$12.6 billion) from the government to allow the effective nationalization of the company. TEPCO is facing a financial crunch with mammoth compensation claims from residents and businesses in the wake of the Fukushima accident.

The estimated cost for compensation and the cleanup operation amounts to more than 100 billion yen (US$1.25 billion), according to TEPCO, Fukushima Daiichi's operator.

Dozens of protesters also gathered outside the TEPCO meeting calling for shareholders and investors to vote for a shift away from nuclear energy.

Greenpeace, a vocal environment group, set up a banner that said: "Meltdown of stock prices. Go to Natural Energy!"

In a statement, Greenpeace activist Ayako Sekine said: "Nuclear power has been disastrous for Japan's environment, the health of its people and its economy."

"Investors face a huge financial risk if they allow themselves to be tricked into believing this disaster is a one-off hiccup."